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1.
N Engl J Med ; 384(11): 1003-1014, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33730454

RESUMO

BACKGROUND: Whether a broadly neutralizing antibody (bnAb) can be used to prevent human immunodeficiency virus type 1 (HIV-1) acquisition is unclear. METHODS: We enrolled at-risk cisgender men and transgender persons in the Americas and Europe in the HVTN 704/HPTN 085 trial and at-risk women in sub-Saharan Africa in the HVTN 703/HPTN 081 trial. Participants were randomly assigned to receive, every 8 weeks, infusions of a bnAb (VRC01) at a dose of either 10 or 30 mg per kilogram (low-dose group and high-dose group, respectively) or placebo, for 10 infusions in total. HIV-1 testing was performed every 4 weeks. The VRC01 80% inhibitory concentration (IC80) of acquired isolates was measured with the TZM-bl assay. RESULTS: Adverse events were similar in number and severity among the treatment groups within each trial. Among the 2699 participants in HVTN 704/HPTN 085, HIV-1 infection occurred in 32 in the low-dose group, 28 in the high-dose group, and 38 in the placebo group. Among the 1924 participants in HVTN 703/HPTN 081, infection occurred in 28 in the low-dose group, 19 in the high-dose group, and 29 in the placebo group. The incidence of HIV-1 infection per 100 person-years in HVTN 704/HPTN 085 was 2.35 in the pooled VRC01 groups and 2.98 in the placebo group (estimated prevention efficacy, 26.6%; 95% confidence interval [CI], -11.7 to 51.8; P = 0.15), and the incidence per 100 person-years in HVTN 703/HPTN 081 was 2.49 in the pooled VRC01 groups and 3.10 in the placebo group (estimated prevention efficacy, 8.8%; 95% CI, -45.1 to 42.6; P = 0.70). In prespecified analyses pooling data across the trials, the incidence of infection with VRC01-sensitive isolates (IC80 <1 µg per milliliter) per 100 person-years was 0.20 among VRC01 recipients and 0.86 among placebo recipients (estimated prevention efficacy, 75.4%; 95% CI, 45.5 to 88.9). The prevention efficacy against sensitive isolates was similar for each VRC01 dose and trial; VRC01 did not prevent acquisition of other HIV-1 isolates. CONCLUSIONS: VRC01 did not prevent overall HIV-1 acquisition more effectively than placebo, but analyses of VRC01-sensitive HIV-1 isolates provided proof-of-concept that bnAb prophylaxis can be effective. (Supported by the National Institute of Allergy and Infectious Diseases; HVTN 704/HPTN 085 and HVTN 703/HPTN 081 ClinicalTrials.gov numbers, NCT02716675 and NCT02568215.).


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Amplamente Neutralizantes/uso terapêutico , Anticorpos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , HIV-1 , Adolescente , Adulto , África Subsaariana/epidemiologia , América/epidemiologia , Anticorpos Monoclonais/efeitos adversos , Anticorpos Amplamente Neutralizantes/efeitos adversos , Método Duplo-Cego , Europa (Continente)/epidemiologia , Feminino , Anticorpos Anti-HIV/efeitos adversos , Infecções por HIV/epidemiologia , HIV-1/efeitos dos fármacos , Humanos , Incidência , Masculino , Estudo de Prova de Conceito , Adulto Jovem
2.
N Engl J Med ; 381(3): 207-218, 2019 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-31314965

RESUMO

BACKGROUND: A universal testing and treatment strategy is a potential approach to reduce the incidence of human immunodeficiency virus (HIV) infection, yet previous trial results are inconsistent. METHODS: In the HPTN 071 (PopART) community-randomized trial conducted from 2013 through 2018, we randomly assigned 21 communities in Zambia and South Africa (total population, approximately 1 million) to group A (combination prevention intervention with universal antiretroviral therapy [ART]), group B (the prevention intervention with ART provided according to local guidelines [universal since 2016]), or group C (standard care). The prevention intervention included home-based HIV testing delivered by community workers, who also supported linkage to HIV care and ART adherence. The primary outcome, HIV incidence between months 12 and 36, was measured in a population cohort of approximately 2000 randomly sampled adults (18 to 44 years of age) per community. Viral suppression (<400 copies of HIV RNA per milliliter) was assessed in all HIV-positive participants at 24 months. RESULTS: The population cohort included 48,301 participants. Baseline HIV prevalence was 21% or 22% in each group. Between months 12 and 36, a total of 553 new HIV infections were observed during 39,702 person-years (1.4 per 100 person-years; women, 1.7; men, 0.8). The adjusted rate ratio for group A as compared with group C was 0.93 (95% confidence interval [CI], 0.74 to 1.18; P = 0.51) and for group B as compared with group C was 0.70 (95% CI, 0.55 to 0.88; P = 0.006). The percentage of HIV-positive participants with viral suppression at 24 months was 71.9% in group A, 67.5% in group B, and 60.2% in group C. The estimated percentage of HIV-positive adults in the community who were receiving ART at 36 months was 81% in group A and 80% in group B. CONCLUSIONS: A combination prevention intervention with ART provided according to local guidelines resulted in a 30% lower incidence of HIV infection than standard care. The lack of effect with universal ART was unanticipated and not consistent with the data on viral suppression. In this trial setting, universal testing and treatment reduced the population-level incidence of HIV infection. (Funded by the National Institute of Allergy and Infectious Diseases and others; HPTN 071 [PopArt] ClinicalTrials.gov number, NCT01900977.).


Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Administração Massiva de Medicamentos , Programas de Rastreamento , Adolescente , Adulto , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Incidência , Masculino , Prevalência , África do Sul/epidemiologia , Carga Viral , Adulto Jovem , Zâmbia/epidemiologia
3.
Bioscience ; 71(10): 1079-1090, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34616238

RESUMO

A growing number of companies have announced zero-deforestation commitments (ZDCs) to eliminate commodities produced at the expense of forests from their supply chains. Translating these aspirational goals into forest conservation requires forest mapping and monitoring (M&M) systems that are technically adequate and therefore credible, salient so that they address the needs of decision makers, legitimate in that they are fair and unbiased, and scalable over space and time. We identify 12 attributes of M&M that contribute to these goals and assess how two prominent ZDC programs, the Amazon Soy Moratorium and the High Carbon Stock Approach, integrate these attributes into their M&M systems. These programs prioritize different attributes, highlighting fundamental trade-offs in M&M design. Rather than prescribe a one-size-fits-all solution, we provide policymakers and practitioners with guidance on the design of ZDC M&M systems that fit their specific use case and that may contribute to more effective implementation of ZDCs.

4.
Proc Natl Acad Sci U S A ; 115(1): 121-126, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29229857

RESUMO

Many major corporations and countries have made commitments to purchase or produce only "sustainable" palm oil, a commodity responsible for substantial tropical forest loss. Sustainability certification is the tool most used to fulfill these procurement policies, and around 20% of global palm oil production was certified by the Roundtable on Sustainable Palm Oil (RSPO) in 2017. However, the effect of certification on deforestation in oil palm plantations remains unclear. Here, we use a comprehensive dataset of RSPO-certified and noncertified oil palm plantations (∼188,000 km2) in Indonesia, the leading producer of palm oil, as well as annual remotely sensed metrics of tree cover loss and fire occurrence, to evaluate the impact of certification on deforestation and fire from 2001 to 2015. While forest loss and fire continued after RSPO certification, certified palm oil was associated with reduced deforestation. Certification lowered deforestation by 33% from a counterfactual of 9.8 to 6.6% y-1 Nevertheless, most plantations contained little residual forest when they received certification. As a result, by 2015, certified areas held less than 1% of forests remaining within Indonesian oil palm plantations. Moreover, certification had no causal impact on forest loss in peatlands or active fire detection rates. Broader adoption of certification in forested regions, strict requirements to avoid all peat, and routine monitoring of clearly defined forest cover loss in certified and RSPO member-held plantations appear necessary if the RSPO is to yield conservation and climate benefits from reductions in tropical deforestation.


Assuntos
Conservação dos Recursos Naturais , Produção Agrícola , Magnoliopsida/crescimento & desenvolvimento , Óleo de Palmeira , Incêndios Florestais , Indonésia
5.
Lancet ; 392(10149): 747-759, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30191830

RESUMO

BACKGROUND: People who inject drugs (PWID) have a high incidence of HIV, little access to antiretroviral therapy (ART) and medication-assisted treatment (MAT), and high mortality. We aimed to assess the feasibility of a future controlled trial based on the incidence of HIV, enrolment, retention, and uptake of the intervention, and the efficacy of an integrated and flexible intervention on ART use, viral suppression, and MAT use. METHODS: This randomised, controlled vanguard study was run in Kyiv, Ukraine (one community site), Thai Nguyen, Vietnam (two district health centre sites), and Jakarta, Indonesia (one hospital site). PWID who were HIV infected (index participants) and non-infected injection partners were recruited as PWID network units and were eligible for screening if they were aged 18-45 years (updated to 18-60 years 8 months into study), and active injection drug users. Further eligibility criteria for index participants included a viral load of 1000 copies per mL or higher, willingness and ability to recruit at least one injection partner who would be willing to participate. Index participants were randomly assigned via a computer generated sequence accessed through a secure web portal (3:1) to standard of care or intervention, stratified by site. Masking of assignment was not possible due to the nature of intervention. The intervention comprised systems navigation, psychosocial counselling, and ART at any CD4 count. Local ART and MAT services were used. Participants were followed up for 12-24 months. The primary objective was to assess the feasibility of a future randomised controlled trial. To achieve this aim we looked at the following endpoints: HIV incidence among injection partners in the standard of care group, and enrolment and retention of HIV-infected PWID and their injection partners and the uptake of the integrated intervention. The study was also designed to assess the feasibility, barriers, and uptake of the integrated intervention. Endpoints were assessed in a modified intention-to-treat popualtion after exclusion of ineligible participants. This trial is registered on ClinicalTrials.gov, NCT02935296, and is active but not recruiting new participants. FINDINGS: Between Feb 5, 2015, and June 3, 2016, 3343 potential index participants were screened, of whom 502 (15%) were eligible and enrolled. 1171 injection partners were referred, and 806 (69%) were eligible and enrolled. Index participants were randomly assigned to intervention (126 [25%]) and standard of care (376 [75%]) groups. At week 52, most living index participants (389 [86%] of 451) and partners (567 [80%] of 710) were retained, and self-reported ART use was higher among index participants in the intervention group than those in the standard of care group (probability ratio [PR] 1·7, 95% CI 1·4-1·9). Viral suppression was also higher in the intervention group than in the standard of care group (PR 1·7, 95% CI 1·3-2·2). Index participants in the intervention group reported more MAT use at 52 weeks than those in the standard of care group (PR 1·7, 95% CI 1·3-2·2). Seven incident HIV infections occurred, and all in injection partners in the standard of care group (intervention incidence 0·0 per 100 person-years, 95% CI 0·0-1·7; standard of care incidence 1·0 per 100 person-years, 95% CI 0·4-2·1; incidence rate difference -1·0 per 100 person-years, 95% CI -2·1 to 1·1). No severe adverse events due to the intervention were recorded. INTERPRETATION: This vanguard study provides evidence that a flexible, scalable intervention increases ART and MAT use and reduces mortality among PWID. The low incidence of HIV in both groups impedes a future randomised, controlled trial, but given the strength of the effect of the intervention, its implementation among HIV-infected PWID should be considered. FUNDING: US National Institutes of Health.


Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Tratamento de Substituição de Opiáceos/métodos , Abuso de Substâncias por Via Intravenosa/tratamento farmacológico , Carga Viral/efeitos dos fármacos , Adulto , Contagem de Linfócito CD4 , Aconselhamento , Estudos de Viabilidade , Feminino , Infecções por HIV/complicações , Infecções por HIV/mortalidade , Humanos , Incidência , Indonésia , Masculino , Metadona/uso terapêutico , Modelos de Riscos Proporcionais , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/mortalidade , Ucrânia , Vietnã , Adulto Jovem
7.
Curr HIV/AIDS Rep ; 11(4): 393-403, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25283184

RESUMO

Treatment as prevention is expected to have a major role in reducing HIV incidence, but other prevention interventions will also be required to bring the epidemic under control, particularly among key populations. One or more forms of pre-exposure prophylaxis (PrEP) will likely play a critical role. Oral PrEP with emtricitabine-tenofovir (Truvada®) is currently available in the US and some other countries, but uptake has been slow. We review the concerns that have contributed to this slow uptake and discuss current and future research in this critical area of HIV prevention research.


Assuntos
Antirretrovirais/administração & dosagem , Desoxicitidina/análogos & derivados , Infecções por HIV/prevenção & controle , Compostos Organofosforados/administração & dosagem , Profilaxia Pré-Exposição/tendências , Administração Oral , Desoxicitidina/administração & dosagem , Combinação de Medicamentos , Combinação Emtricitabina e Fumarato de Tenofovir Desoproxila , Feminino , Humanos , Masculino , Profilaxia Pré-Exposição/economia
8.
Lancet Microbe ; 5(1): e62-e71, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38081203

RESUMO

BACKGROUND: In the last decade, universally available antiretroviral therapy (ART) has led to greatly improved health and survival of people living with HIV in sub-Saharan Africa, but new infections continue to appear. The design of effective prevention strategies requires the demographic characterisation of individuals acting as sources of infection, which is the aim of this study. METHODS: Between 2014 and 2018, the HPTN 071 PopART study was conducted to quantify the public health benefits of ART. Viral samples from 7124 study participants in Zambia were deep-sequenced as part of HPTN 071-02 PopART Phylogenetics, an ancillary study. We used these sequences to identify likely transmission pairs. After demographic weighting of the recipients in these pairs to match the overall HIV-positive population, we analysed the demographic characteristics of the sources to better understand transmission in the general population. FINDINGS: We identified a total of 300 likely transmission pairs. 178 (59·4%) were male to female, with 130 (95% CI 110-150; 43·3%) from males aged 25-40 years. Overall, men transmitted 2·09-fold (2·06-2·29) more infections per capita than women, a ratio peaking at 5·87 (2·78-15·8) in the 35-39 years source age group. 40 (26-57; 13·2%) transmissions linked individuals from different communities in the trial. Of 288 sources with recorded information on drug resistance mutations, 52 (38-69; 18·1%) carried viruses resistant to first-line ART. INTERPRETATION: HIV-1 transmission in the HPTN 071 study communities comes from a wide range of age and sex groups, and there is no outsized contribution to new infections from importation or drug resistance mutations. Men aged 25-39 years, underserved by current treatment and prevention services, should be prioritised for HIV testing and ART. FUNDING: National Institute of Allergy and Infectious Diseases, US President's Emergency Plan for AIDS Relief, International Initiative for Impact Evaluation, Bill & Melinda Gates Foundation, National Institute on Drug Abuse, and National Institute of Mental Health.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Adulto , Feminino , Humanos , Masculino , Demografia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , HIV-1/genética , Epidemiologia Molecular , Estados Unidos , Zâmbia/epidemiologia
9.
N Engl J Med ; 363(27): 2587-99, 2010 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-21091279

RESUMO

BACKGROUND: Antiretroviral chemoprophylaxis before exposure is a promising approach for the prevention of human immunodeficiency virus (HIV) acquisition. METHODS: We randomly assigned 2499 HIV-seronegative men or transgender women who have sex with men to receive a combination of two oral antiretroviral drugs, emtricitabine and tenofovir disoproxil fumarate (FTC-TDF), or placebo once daily. All subjects received HIV testing, risk-reduction counseling, condoms, and management of sexually transmitted infections. RESULTS: The study subjects were followed for 3324 person-years (median, 1.2 years; maximum, 2.8 years). Of these subjects, 10 were found to have been infected with HIV at enrollment, and 100 became infected during follow-up (36 in the FTC-TDF group and 64 in the placebo group), indicating a 44% reduction in the incidence of HIV (95% confidence interval, 15 to 63; P=0.005). In the FTC-TDF group, the study drug was detected in 22 of 43 of seronegative subjects (51%) and in 3 of 34 HIV-infected subjects (9%) (P<0.001). Nausea was reported more frequently during the first 4 weeks in the FTC-TDF group than in the placebo group (P<0.001). The two groups had similar rates of serious adverse events (P=0.57). CONCLUSIONS: Oral FTC-TDF provided protection against the acquisition of HIV infection among the subjects. Detectable blood levels strongly correlated with the prophylactic effect. (Funded by the National Institutes of Health and the Bill and Melinda Gates Foundation; ClinicalTrials.gov number, NCT00458393.).


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/uso terapêutico , Desoxicitidina/análogos & derivados , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Organofosfonatos/uso terapêutico , Adenina/efeitos adversos , Adenina/sangue , Adenina/uso terapêutico , Administração Oral , Adolescente , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/sangue , Desoxicitidina/efeitos adversos , Desoxicitidina/sangue , Desoxicitidina/uso terapêutico , Farmacorresistência Viral , Quimioterapia Combinada , Emtricitabina , Seguimentos , HIV/genética , HIV/isolamento & purificação , Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Soropositividade para HIV/diagnóstico , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Organofosfonatos/efeitos adversos , Organofosfonatos/sangue , Cooperação do Paciente , RNA Viral/sangue , Tenofovir , Transexualidade , Adulto Jovem
10.
J Acquir Immune Defic Syndr ; 89(4): 405-413, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34923559

RESUMO

BACKGROUND: The antibody-mediated prevention (AMP) studies (HVTN 703/HPTN 081 and HVTN 704/HPTN 085) are harmonized phase 2b trials to assess HIV prevention efficacy and safety of intravenous infusion of anti-gp120 broadly neutralizing antibody VRC01. Antibodies for other indications can elicit infusion-related reactions (IRRs), often requiring premedication and limiting their application. We report on AMP study IRRs. METHODS: From 2016 to 2018, 2699 HIV-uninfected, at-risk men and transgender adults in the Americas and Switzerland (704/085) and 1924 at-risk heterosexual women in sub-Saharan Africa (703/081) were randomized 1:1:1 to VRC01 10 mg/kg, 30 mg/kg, or placebo. Participants received infusions every 8 weeks (n = 10/participant) over 72 weeks, with 104 weeks of follow-up. Safety assessments were conducted before and after infusion and at noninfusion visits. A total of 40,674 infusions were administered. RESULTS: Forty-seven participants (1.7%) experienced 49 IRRs in 704/085; 93 (4.8%) experienced 111 IRRs in 703/081 (P < 0.001). IRRs occurred more frequently in VRC01 than placebo recipients in 703/081 (P < 0.001). IRRs were associated with atopic history (P = 0.046) and with younger age (P = 0.023) in 703/081. Four clinical phenotypes of IRRs were observed: urticaria, dyspnea, dyspnea with rash, and "other." Urticaria was most prevalent, occurring in 25 (0.9%) participants in 704/085 and 41 (2.1%) participants in 703/081. Most IRRs occurred with the initial infusion and incidence diminished through the last infusion. All reactions were managed successfully without sequelae. CONCLUSIONS: IRRs in the AMP studies were uncommon, typically mild or moderate, successfully managed at the research clinic, and resolved without sequelae. Analysis is ongoing to explore potential IRR mechanisms.


Assuntos
Infecções por HIV , HIV-1 , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes , Anticorpos Amplamente Neutralizantes , Feminino , Anticorpos Anti-HIV , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Open Forum Infect Dis ; 8(8): ofab281, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34458390

RESUMO

BACKGROUND: People who inject drugs (PWID) living with HIV experience inadequate access to antiretroviral treatment (ART) and medication for opioid use disorders (MOUD). HPTN 074 showed that an integrated intervention increased ART use and viral suppression over 52 weeks. To examine durability of ART, MOUD, and HIV viral suppression, participants could re-enroll for an extended follow-up period, during which standard-of-care (SOC) participants in need of support were offered the intervention. METHODS: Participants were recruited from Ukraine, Indonesia and Vietnam and randomly allocated 3:1 to SOC or intervention. Eligibility criteria included: HIV-positive; active injection drug use; 18-60 years of age; ≥1 HIV-uninfected injection partner; and viral load ≥1,000 copies/mL. Re-enrollment was offered to all available intervention and SOC arm participants, and SOC participants in need of support (off-ART or off-MOUD) were offered the intervention. RESULTS: The intervention continuation group re-enrolled 89 participants, and from week 52 to 104, viral suppression (<40 copies/mL) declined from 41% to 29% (estimated 9.4% decrease per year, 95% CI -17.0%; -1.8%). The in need of support group re-enrolled 94 participants and had increased ART (re-enrollment: 55%, week 26: 69%) and MOUD (re-enrollment: 16%, week 26: 25%) use, and viral suppression (re-enrollment: 40%, week 26: 49%). CONCLUSIONS: Viral suppression declined in year 2 for those who initially received the HPTN 074 intervention and improved maintenance support is warranted. Viral suppression and MOUD increased among in need participants who received intervention during the study extension. Continued efforts are needed for widespread implementation of this scalable, integrated intervention.

12.
Clin Infect Dis ; 51(6): 725-31, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20707698

RESUMO

Research on the prevention of human immunodeficiency virus (HIV)-1 infection is at a critical juncture. Major methodological challenges to performing prevention trials have emerged, and one after another promising biomedical interventions have failed to reduce the incidence of HIV-1 infection. Nevertheless, there is growing optimism that progress can be achieved in the near term. Mathematical modeling indicates that 2 new strategies, "test and treat" and preexposure prophylaxis, could have a major impact on the incidence of HIV-1 infection. Will our hopes be justified? We review the potential strengths and limitations of these antiretroviral "treatment as prevention" strategies and outline other new options for reducing the incidence of HIV-1 infection in the near term. By maximizing the potential of existing interventions, developing other effective strategies, and combining them in an optimal manner, we have the opportunity to bring the HIV-1 epidemic under control.


Assuntos
Controle de Doenças Transmissíveis/métodos , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , HIV-1/isolamento & purificação , Pandemias , Fármacos Anti-HIV/uso terapêutico , Quimioprevenção/métodos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Incidência , Modelos Teóricos
13.
J Int AIDS Soc ; 21(10): e25195, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30350406

RESUMO

INTRODUCTION: People who inject drugs (PWID) experience high HIV incidence and face significant barriers to engagement in HIV care and substance use treatment. Strategies for HIV treatment as prevention and substance use treatment present unique challenges in PWID that may vary regionally. Understanding differences in the risk structure for HIV transmission and disease progression among PWID is essential in developing and effectively targeting intervention strategies of HIV treatment as prevention. METHODS: We present a baseline analysis of HIV Prevention Trials Network (HPTN) 074, a two-arm, randomized controlled trial among PWID in Indonesia (n = 258), Ukraine (n = 457) and Vietnam (n = 439). HPTN 074 was designed to determine the feasibility, barriers and uptake of an integrated intervention combining health systems navigation and psychosocial counselling for the early engagement of antiretroviral therapy (ART) and substance use treatment for PWID living with HIV. Discordant PWID networks were enrolled, consisting of an HIV-positive index and their HIV-negative network injection partner(s). Among the enrolled cohort of 1154 participants (502 index participants and 652 network partners), we examine regional differences in the baseline risk structure, including sociodemographics, HIV and substance use treatment history, and injection and sexual risk behaviours. RESULTS: The majority of participants were male (87%), with 82% of the enrolled females coming from Ukraine. The overall mean age was 34 (IQR: 30, 38). Most commonly injected substances included illegally manufactured methadone in Ukraine (84.2%), and heroin in Indonesia (81.8%) and Vietnam (99.5%). Injection network sizes varied by region: median number of people with whom participants self-reported injecting drugs was 3 (IQR: 2, 5) in Indonesia, 5 (IQR: 3, 10) in Ukraine and 3 (IQR: 2, 4) in Vietnam. Hazardous alcohol use, assessed using the Alcohol Use Disorders Identification Test - Alcohol Consumption Questions (AUDIT-C), was prominent in Ukraine (54.7%) and Vietnam (26.4%). Reported sexual risk behaviours in the past month, including having two or more sex partners and giving/receiving money or drugs in exchange for sex, were uncommon among all participants and regions. CONCLUSIONS: While regional differences in risk structure exist, PWID particularly in Ukraine need immediate attention for risk reduction strategies. Substantial regional differences in risk structure will require flexible, tailored treatment as prevention interventions for distinct PWID populations.


Assuntos
Infecções por HIV/tratamento farmacológico , Abuso de Substâncias por Via Intravenosa/complicações , Adolescente , Adulto , Contagem de Linfócito CD4 , Estudos de Coortes , Feminino , Infecções por HIV/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Comportamento Sexual , Carga Viral , Adulto Jovem
14.
Stat Commun Infect Dis ; 9(1)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29218117

RESUMO

BACKGROUND: Anti-HIV-1 broadly neutralizing antibodies (bnAbs) have been developed as potential agents for prevention of HIV-1 infection. The HIV Vaccine Trials Network and the HIV Prevention Trials Network are conducting the Antibody Mediated Prevention (AMP) trials to assess whether, and how, intravenous infusion of the anti-CD4 binding site bnAb, VRC01, prevents HIV-1 infection. These are the first test-of-concept studies to assess HIV-1 bnAb prevention efficacy in humans. METHODS: The AMP trials are two parallel phase 2b HIV-1 prevention efficacy trials conducted in two cohorts: 2700 HIV-uninfected men and transgender persons who have sex with men in the United States, Peru, Brazil, and Switzerland; and 1500 HIV-uninfected sexually active women in seven countries in sub-Saharan Africa. Participants are randomized 1:1:1 to receive an intravenous infusion of 10 mg/kg VRC01, 30 mg/kg VRC01, or a control preparation every 8 weeks for a total of 10 infusions. Each trial is designed (1) to assess overall prevention efficacy (PE) pooled over the two VRC01 dose groups vs. control and (2) to assess VRC01 dose and laboratory markers as correlates of protection (CoPs) against overall and genotype- and phenotype-specific infection. RESULTS: Each AMP trial is designed to have 90% power to detect PE > 0% if PE is ≥ 60%. The AMP trials are also designed to identify VRC01 properties (i.e., concentration and effector functions) that correlate with protection and to provide insight into mechanistic CoPs. CoPs are assessed using data from breakthrough HIV-1 infections, including genetic sequences and sensitivities to VRC01-mediated neutralization and Fc effector functions. CONCLUSIONS: The AMP trials test whether VRC01 can prevent HIV-1 infection in two study populations. If affirmative, they will provide information for estimating the optimal dosage of VRC01 (or subsequent derivatives) and identify threshold levels of neutralization and Fc effector functions associated with high-level protection, setting a benchmark for future vaccine evaluation and constituting a bridge to other bnAb approaches for HIV-1 prevention.

15.
J Acquir Immune Defic Syndr ; 68(5): 554-61, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25564105

RESUMO

BACKGROUND: Injection opioid use plays a significant role in the transmission of HIV infection in many communities and several regions of the world. Access to evidence-based treatments for opioid use disorders is extremely limited. METHODS: HIV Prevention Trials Network 058 (HPTN 058) was a randomized controlled trial designed to compare the impact of 2 medication-assisted treatment (MAT) strategies on HIV incidence or death among opioid-dependent people who inject drugs (PWID). HIV-negative opioid-dependent PWID were recruited from 4 communities in Thailand and China with historically high prevalence of HIV among PWID. A total of 1251 participants were randomly assigned to either (1) a 1-year intervention consisting of 2 opportunities for a 15-day detoxification with buprenorphine/naloxone (BUP/NX) combined with up to 21 sessions of behavioral drug and risk counseling [short-term medication-assisted treatment (ST-MAT)] or (2) thrice-weekly dosing for 48 weeks with BUP/NX and up to 21 counseling sessions [long-term medication-assisted treatment (LT-MAT)] followed by dose tapering. All participants were followed for 52 weeks after treatment completion to assess durability of impact. RESULTS: Although the study was stopped early due to lower than expected occurrence of the primary end points, sufficient data were available to assess the impact of the interventions on drug use and injection-related risk behavior. At week 26, 22% of ST-MAT participants had negative urinalyses for opioids compared with 57% in the LT-MAT (P < 0.001). Differences disappeared in the year after treatment: at week 78, 35% in ST-MAT and 32% in the LT-MAT had negative urinalyses. Injection-related risk behaviors were significantly reduced in both groups after randomization. CONCLUSIONS: Participants receiving BUP/NX 3 times weekly were more likely to reduce opioid injection while on active treatment. Both treatment strategies were considered safe and associated with reductions in injection-related risk behavior. These data support the use of thrice-weekly BUP/NX as a way to reduce exposure to HIV risk. Continued access to BUP/NX may be required to sustain reductions in opioid use.


Assuntos
Buprenorfina/uso terapêutico , Infecções por HIV/prevenção & controle , Naloxona/uso terapêutico , Tratamento de Substituição de Opiáceos/métodos , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/terapia , Adulto , Buprenorfina/efeitos adversos , China , Feminino , Humanos , Incidência , Masculino , Naloxona/efeitos adversos , Tratamento de Substituição de Opiáceos/efeitos adversos , Tailândia , Resultado do Tratamento
16.
AIDS Res Hum Retroviruses ; 30(3): 217-24, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24410300

RESUMO

Epidemic modeling suggests that a major scale-up in HIV treatment could have a dramatic impact on HIV incidence. This has led both researchers and policymakers to set a goal of an "AIDS-Free Generation." One of the greatest obstacles to achieving this objective is the number of people with undiagnosed HIV infection. Despite recent innovations, new research strategies are needed to identify, engage, and successfully treat people who are unaware of their infection.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Transmissão de Doença Infecciosa/prevenção & controle , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Necessidades e Demandas de Serviços de Saúde , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos
17.
AIDS ; 28(6): 851-9, 2014 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-24499951

RESUMO

OBJECTIVE: Tenofovir disoproxil fumarate (TDF) pre-exposure prophylaxis decreases sexual acquisition of HIV infection. We sought to evaluate the renal safety of TDF in HIV-uninfected persons. DESIGN AND METHODS: The Iniciativa Profilaxis Pre-Exposición (iPrEx) study randomly assigned 2499 HIV-seronegative men and transgender women who have sex with men (MSM) to receive oral daily TDF coformulated with emtricitabine (FTC/TDF) or placebo. Serum creatinine and phosphorus during randomized treatment and after discontinuation were measured, and creatinine clearance (CrCl) was estimated by the Cockcroft-Gault equation. Indicators of proximal renal tubulopathy (fractional excretion of phosphorus and uric acid, urine protein, and glucose) were measured in a substudy. RESULTS: There was a small but statistically significant decrease in CrCl from baseline in the active arm, compared to placebo, which was first observed at week 4 (mean change: -2.4 vs. -1.1 ml/min; P=0.02), persisted through the last on-treatment visit (mean change: +0.3 vs. +1.8 ml/min; P=0.02), and resolved after stopping pre-exposure prophylaxis (mean change: -0.1 vs. 0.0 ml/min; P=0.83). The effect was confirmed when stratifying by drug detection. The effect of FTC/TDF on CrCl did not vary by race, age, or history of hypertension. There was no difference in serum phosphate trends between the treatment arms. In the substudy, two participants receiving placebo had indicators of tubulopathy. CONCLUSIONS: In HIV-seronegative MSM, randomization to FTC/TDF was associated with a very mild nonprogressive decrease in CrCl that was reversible and managed with routine serum creatinine monitoring.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/uso terapêutico , Quimioprevenção/métodos , Desoxicitidina/análogos & derivados , Infecções por HIV/prevenção & controle , Testes de Função Renal , Rim/fisiologia , Organofosfonatos/uso terapêutico , Adenina/efeitos adversos , Adenina/uso terapêutico , Adolescente , Adulto , Fármacos Anti-HIV/efeitos adversos , Quimioprevenção/efeitos adversos , Creatinina/sangue , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Emtricitabina , Feminino , Humanos , Rim/efeitos dos fármacos , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Organofosfonatos/efeitos adversos , Fósforo/sangue , Placebos/administração & dosagem , Tenofovir , Adulto Jovem
18.
Lancet Infect Dis ; 14(9): 820-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25065857

RESUMO

BACKGROUND: The effect of HIV pre-exposure prophylaxis (PrEP) depends on uptake, adherence, and sexual practices. We aimed to assess these factors in a cohort of HIV-negative people at risk of infection. METHODS: In our cohort study, men and transgender women who have sex with men previously enrolled in PrEP trials (ATN 082, iPrEx, and US Safety Study) were enrolled in a 72 week open-label extension. We measured drug concentrations in plasma and dried blood spots in seroconverters and a random sample of seronegative participants. We assessed PrEP uptake, adherence, sexual practices, and HIV incidence. Statistical methods included Poisson models, comparison of proportions, and generalised estimating equations. FINDINGS: We enrolled 1603 HIV-negative people, of whom 1225 (76%) received PrEP. Uptake was higher among those reporting condomless receptive anal intercourse (416/519 [81%] vs 809/1084 [75%], p=0·003) and having serological evidence of herpes (612/791 [77%] vs 613/812 [75%] p=0·03). Of those receiving PrEP, HIV incidence was 1·8 infections per 100 person-years, compared with 2·6 infections per 100 person-years in those who concurrently did not choose PrEP (HR 0·51, 95% CI 0·26-1·01, adjusted for sexual behaviours), and 3·9 infections per 100 person-years in the placebo group of the previous randomised phase (HR 0·49, 95% CI 0·31-0·77). Among those receiving PrEP, HIV incidence was 4·7 infections per 100 person-years if drug was not detected in dried blood spots, 2·3 infections per 100 person-years if drug concentrations suggested use of fewer than two tablets per week, 0·6 per 100 person-years for use of two to three tablets per week, and 0·0 per 100 person-years for use of four or more tablets per week (p<0·0001). PrEP drug concentrations were higher among people of older age, with more schooling, who reported non-condom receptive anal intercourse, who had more sexual partners, and who had a history of syphilis or herpes. INTERPRETATION: PrEP uptake was high when made available free of charge by experienced providers. The effect of PrEP is increased by greater uptake and adherence during periods of higher risk. Drug concentrations in dried blood spots are strongly correlated with protective benefit. FUNDING: US National Institutes of Health.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Comportamento Sexual , Pessoas Transgênero , Adolescente , Adulto , Fármacos Anti-HIV/sangue , Estudos de Coortes , Feminino , Infecções por HIV/epidemiologia , Humanos , Incidência , Masculino
19.
AIDS Res Hum Retroviruses ; 28(6): 532-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22206265

RESUMO

Reliable methods for measuring human immunodeficiency virus (HIV) incidence are a high priority for HIV prevention. They are particularly important to assess the population-level effectiveness of new prevention strategies, to evaluate the community-wide impact of ongoing prevention programs, and to assess whether a proposed prevention trial can be performed in a timely and cost-efficient manner in a particular population and setting. New incidence assays and algorithms that are accurate, rapid, cost-efficient, and can be performed on easily-obtained specimens are urgently needed. On May 4, 2011, the Division of AIDS (DAIDS), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), sponsored a 1-day workshop to examine strategies for developing new assays to distinguish recent from chronic HIV infections. Participants included leading investigators, clinicians, public health experts, industry, regulatory specialists, and other stakeholders. Immune-based parameters, markers of viral sequence diversity, and other biomarkers such as telomere length were evaluated. Emerging nanotechnology and chip-based diagnostics, including algorithms for performing diverse assays on a single platform, were also reviewed. This report summarizes the presentations, panel discussions, and the consensus reached for pursuing the development of a new generation of HIV incidence assays.


Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , Imunoglobulina A/imunologia , Homeostase do Telômero/imunologia , Algoritmos , Biomarcadores/sangue , Relação CD4-CD8 , Análise Custo-Benefício , Feminino , Variação Genética , Infecções por HIV/genética , Infecções por HIV/prevenção & controle , Humanos , Imunoglobulina A/genética , Incidência , Masculino , National Institute of Allergy and Infectious Diseases (U.S.) , National Institutes of Health (U.S.) , Avaliação das Necessidades , Homeostase do Telômero/genética , Estados Unidos
20.
AIDS ; 26(18): 2267-73, 2012 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-22569019

RESUMO

OBJECTIVE: To review the evidence for antiretroviral 'treatment as prevention' for HIV transmission among MSM. METHODS: We reviewed studies that assess the biological plausibility that virally suppressive antiretroviral therapy (ART) reduces HIV infectiousness via anal intercourse and the epidemiologic evidence of whether ART has played a role in attenuating HIV incidence among MSM. RESULTS: Although ART treatment among MSM is likely to provide some preventive benefit, it is unknown whether it will reduce HIV infectiousness via anal intercourse to the same extent as via penile-vaginal intercourse. Additional research is needed on the pharmacokinetic properties of specific antiretroviral agents in the gastrointestinal tract. Estimates of risk behaviors and the incidence of HIV among MSM before and after the introduction and expansion of ART suggest that the population-level protective benefits of ART may be attenuated by a number of factors, most notably, continuing or increasing frequency of condomless anal intercourse and incidence of other sexually transmitted infections (STIs). Additional studies are needed on the impact of ART on HIV sexual risk behaviors and transmission among MSM outside of developed countries in North America, western Europe, and Australia. CONCLUSION: The benefits of treatment as prevention for MSM are highly plausible, but not certain. In the face of these unknowns, treatment guidelines for earlier ART initiation should be considered within a combination prevention strategy that includes earlier diagnosis, expanded STI treatment, and structural and behavioral interventions.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Comportamento Sexual/estatística & dados numéricos , Austrália/epidemiologia , Europa (Continente)/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Conhecimentos, Atitudes e Prática em Saúde , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Incidência , Masculino , América do Norte/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco
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